Theoretically only water ought to be present in the evaporator compartment. In practice some lithium bromide is carried over from the absorber or from the condenser and if this accumulates, the effect is one of reduction of efficiency of the chiller. It is thus necessary to remove from time to time the dilute lithium bromide solution and to replace it by water. Furthermore, noncondensables tend to accumulate and these too have to be removed from time to time.
In systems using a high concentration lithium bromide solution, when the chiller was shut down overnight, there has to be added water or dilute lithium bromide solution to the absorber compartment when the chiller was activated again.
Hitherto there was generally provided a conduit from the bottom of the evaporator to an appropriate location in the lithium bromide circuit.
The exit from the evaporator was generally provided with a valve and when this was not tightly closed, even a small leakage caused serious problems. In order to avoid such leakages the valves were often closed too tightly and this too causes sometimes leakages.